Change the voltage property of the sensor from 0 to 25 while the simulation is running. You will see the Serial Monitor reading change in real-time. This confirms the Voltage Sensor Proteus Library UPD is working correctly.

| Problem | Likely Cause | Solution | |---------|--------------|----------| | No output | Missing SPICE model | Ensure you used Simulator Primitives (not generic parts) | | Output stuck at 0V | Floating ground | Connect GND pin to circuit ground | | Non-linear output | Op-amp saturation | Check power supply to op-amp (e.g., +12V/-12V) | | Library part not found | Wrong folder | Move files to active library path (System → Set Paths) |

For measuring voltages that do not share a common ground (differential measurement), Proteus users model a Difference Amplifier topology using Op-Amps. This subtracts a reference voltage and amplifies the difference.

: Move files from your download's /LIBRARY folder into the LIBRARY folder in the Proteus directory.